Online shopping saves time and provides an enormous product choice, which can be especially convenient during the Christmas shopping season. According to a German market study, six percent of all fresh foods sold today are purchased online - and this rate is on the rise. For perishable foods, however, it is necessary to follow certain hygienic rules.

Dagmar Schoder from the Institute of Milk Hygiene at the Vetmeduni Vienna was interested above all in one especially high-risk food - raw milk cheese. Raw milk cheeses are made from unpasteurised milk, which puts them at a higher risk of microbiological contamination.

Over 100 cheese products tested

Schoder and her colleagues ordered 108 different raw milk cheeses from 21 online retailers in seven European countries (France, Italy, the Netherlands, Germany, Switzerland, Spain and Belgium). "We chose raw milk cheese because it is a high-risk product. As raw milk is unpasteurised, it can be easily contaminated with harmful bacteria. Even a small amount of bacteria, for which raw milk cheese offers ideal growing conditions, can reach critical proportions after a longer ripening, storage and transport time. The product is then no longer edible and may even make consumers ill. For this reason, special care must be taken during production, storage and transport," says Schoder.

Pathogenic and faecal bacteria found in cheese samples

The researchers found Listeria monocytogenes in two cheese products: one from France and one from the Netherlands. An infection with Listeria monocytogenes can be dangerous mainly for immuno-compromised individuals and pregnant women. Listeriosis is a reportable disease in Austria which in extreme cases may even be fatal. The faecal bacteria Escherichia coli was found in 32 products. It indicates poor conditions of hygiene during production. Salmonella were not found in any of the cheese samples.

"Some of the producers apparently have shortcomings in terms of hygiene," says first author Schoder. "Furthermore, when making online purchases, I recommend consumers to check if a product is adequately packaged and cooled when it arrives."

More than half of the products are shipped without proper cooling

The shipping period of the online products was between one and five days. "Cheese must be cooled," Schoder stresses. But this was not the case with 61.5 percent of the raw milk products purchased. "If raw milk cheese is not cooled, bacteria will grow more quickly. A longer transport journey and improper packaging increase the risk for consumers."

Inadequate labelling in over 80 percent of the products

Only 19 cheeses fulfilled the EU labelling requirements (Directive 2000/13/EC and Regulation 853/2004). Of the cheeses purchased, 37 were not labelled as "raw milk cheese" and 43 labels had no "use by date". Information on storage requirements was missing in more than half of the cheeses.